Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-07-14
Astrophys.J.633:424-439,2005
Astronomy and Astrophysics
Astrophysics
24 pages, 8 figures, accepted for publication in the Astrophysical Journal
Scientific paper
10.1086/452622
We have fit synthetic visibilities from 3-D (CO5BOLD + PHOENIX) and 1-D (PHOENIX, ATLAS 12) model stellar atmospheres of Procyon (F5 IV) to high-precision interferometric data from the VLTI Interferometer (K-band) and from the Mark III interferometer (500 nm and 800 nm). These data sets provide a test of theoretical wavelength dependent limb-darkening predictions. The work of Allende Prieto et al. has shown that the temperature structure from a spatially and temporally averaged 3-D hydrodynamical model produces significantly less limb darkening at 500 nm relative to the temperature structure of a 1-D MARCS model atmosphere with a standard mixing-length approximation for convection. Our direct fits to the interferometric data confirm this prediction. A 1-D ATLAS 12 model with ``approximate overshooting'' provides the required temperature gradient. We show, however, that 1-D models cannot reproduce the ultraviolet spectrophotometry below 160 nm with effective temperatures in the range constrained by the measured bolometric flux and angular diameter. We find that a good match to the full spectral energy distribution can be obtained with a composite model consisting of a weighted average of twelve 1-D model atmospheres based on the surface intensity distribution of a 3-D granulation simulation. We emphasize that 1-D models with overshooting may realistically represent the mean temperature structure of F-type stars like Procyon, but the same models will predict redder colors than observed because they lack the multicomponent temperature distribution expected for the surfaces of these stars.
Aufdenberg Jason Paul
Kervella Pierre
Ludwig Hans Günter
No associations
LandOfFree
On the Limb Darkening, Spectral Energy Distribution, and Temperature Structure of Procyon does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with On the Limb Darkening, Spectral Energy Distribution, and Temperature Structure of Procyon, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On the Limb Darkening, Spectral Energy Distribution, and Temperature Structure of Procyon will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-574477